---
ticker: "KRBOKMSB"
title: "South Korea Bank of Korea Monetary Stabilization Bond Outstanding"
unit: "tril. KRW"
frequency: "Monthly"
source: "Bank of Korea (2003)"
release: "Updated Monthly"
category: "Monetary Data"
country: "KR"
language: "en"
canonical: "https://kred.dev/en/series/KRBOKMSB"
license: "https://creativecommons.org/licenses/by-nc-nd/4.0/"
latest_value: 97.27
latest_date: "2026-06-30"
first_date: "1990-01-31"
observations_total: 438
observations_shown: 120
---

# South Korea Bank of Korea Monetary Stabilization Bond Outstanding

## Overview

Debt securities issued by the central bank that sterilize reserve buildup structurally.

## Key Figures

|  | Value | Date |
|---|---|---|
| Latest | 97.27 | 2026-06-30 |
| Change from previous | +2.87 | 2026-05-31 |
| Change over one year | -8.69 | 2025-06-30 |
| Highest on record | 189.29 | 2015-10-31 |
| Lowest on record | 13.86 | 1991-12-31 |
| Period covered | 1990-01-31 – 2026-06-30 |  |
| Observations | 438 |  |

## Recent observations

| Date | Value | Change |
|---|---|---|
| 2016-07-31 | 186.09 | +1.23 |
| 2016-08-31 | 183.89 | -2.20 |
| 2016-09-30 | 183.13 | -0.76 |
| 2016-10-31 | 177.98 | -5.15 |
| 2016-11-30 | 175.35 | -2.63 |
| 2016-12-31 | 168.37 | -6.98 |
| 2017-01-31 | 168.81 | +0.44 |
| 2017-02-28 | 170.44 | +1.63 |
| 2017-03-31 | 174.86 | +4.42 |
| 2017-04-30 | 174.18 | -0.68 |
| 2017-05-31 | 175.21 | +1.03 |
| 2017-06-30 | 174.80 | -0.41 |
| 2017-07-31 | 175.38 | +0.58 |
| 2017-08-31 | 174.43 | -0.95 |
| 2017-09-30 | 166.02 | -8.41 |
| 2017-10-31 | 172.51 | +6.49 |
| 2017-11-30 | 172.05 | -0.46 |
| 2017-12-31 | 170.78 | -1.27 |
| 2018-01-31 | 174.86 | +4.08 |
| 2018-02-28 | 173.01 | -1.85 |
| 2018-03-31 | 174.70 | +1.69 |
| 2018-04-30 | 174.14 | -0.56 |
| 2018-05-31 | 176.99 | +2.85 |
| 2018-06-30 | 174.54 | -2.45 |
| 2018-07-31 | 176.34 | +1.80 |
| 2018-08-31 | 173.95 | -2.39 |
| 2018-09-30 | 174.54 | +0.59 |
| 2018-10-31 | 173.57 | -0.97 |
| 2018-11-30 | 173.41 | -0.16 |
| 2018-12-31 | 171.64 | -1.77 |
| 2019-01-31 | 172.76 | +1.12 |
| 2019-02-28 | 171.45 | -1.31 |
| 2019-03-31 | 171.15 | -0.30 |
| 2019-04-30 | 170.86 | -0.29 |
| 2019-05-31 | 171.26 | +0.40 |
| 2019-06-30 | 171.59 | +0.33 |
| 2019-07-31 | 173.22 | +1.63 |
| 2019-08-31 | 172.97 | -0.25 |
| 2019-09-30 | 170.99 | -1.98 |
| 2019-10-31 | 170.00 | -0.99 |
| 2019-11-30 | 168.74 | -1.26 |
| 2019-12-31 | 164.06 | -4.68 |
| 2020-01-31 | 163.40 | -0.66 |
| 2020-02-29 | 163.99 | +0.59 |
| 2020-03-31 | 165.75 | +1.76 |
| 2020-04-30 | 166.23 | +0.48 |
| 2020-05-31 | 167.26 | +1.03 |
| 2020-06-30 | 168.93 | +1.67 |
| 2020-07-31 | 169.11 | +0.18 |
| 2020-08-31 | 168.72 | -0.39 |
| 2020-09-30 | 166.78 | -1.94 |
| 2020-10-31 | 163.95 | -2.83 |
| 2020-11-30 | 162.46 | -1.49 |
| 2020-12-31 | 159.26 | -3.20 |
| 2021-01-31 | 159.54 | +0.28 |
| 2021-02-28 | 157.57 | -1.97 |
| 2021-03-31 | 157.23 | -0.34 |
| 2021-04-30 | 155.25 | -1.98 |
| 2021-05-31 | 154.62 | -0.63 |
| 2021-06-30 | 154.21 | -0.41 |
| 2021-07-31 | 154.72 | +0.51 |
| 2021-08-31 | 151.75 | -2.97 |
| 2021-09-30 | 150.99 | -0.76 |
| 2021-10-31 | 147.55 | -3.44 |
| 2021-11-30 | 145.11 | -2.44 |
| 2021-12-31 | 140.22 | -4.89 |
| 2022-01-31 | 141.78 | +1.56 |
| 2022-02-28 | 140.89 | -0.89 |
| 2022-03-31 | 140.01 | -0.88 |
| 2022-04-30 | 134.35 | -5.66 |
| 2022-05-31 | 131.69 | -2.66 |
| 2022-06-30 | 125.64 | -6.05 |
| 2022-07-31 | 124.92 | -0.72 |
| 2022-08-31 | 121.47 | -3.45 |
| 2022-09-30 | 122.68 | +1.21 |
| 2022-10-31 | 119.41 | -3.27 |
| 2022-11-30 | 118.71 | -0.70 |
| 2022-12-31 | 112.45 | -6.26 |
| 2023-01-31 | 114.99 | +2.54 |
| 2023-02-28 | 115.04 | +0.05 |
| 2023-03-31 | 121.97 | +6.93 |
| 2023-04-30 | 122.31 | +0.34 |
| 2023-05-31 | 130.79 | +8.48 |
| 2023-06-30 | 124.13 | -6.66 |
| 2023-07-31 | 126.89 | +2.76 |
| 2023-08-31 | 123.00 | -3.89 |
| 2023-09-30 | 125.35 | +2.35 |
| 2023-10-31 | 120.04 | -5.31 |
| 2023-11-30 | 119.91 | -0.13 |
| 2023-12-31 | 121.56 | +1.65 |
| 2024-01-31 | 116.59 | -4.97 |
| 2024-02-29 | 118.23 | +1.64 |
| 2024-03-31 | 119.93 | +1.70 |
| 2024-04-30 | 115.58 | -4.35 |
| 2024-05-31 | 116.87 | +1.29 |
| 2024-06-30 | 119.62 | +2.75 |
| 2024-07-31 | 113.63 | -5.99 |
| 2024-08-31 | 116.94 | +3.31 |
| 2024-09-30 | 113.90 | -3.04 |
| 2024-10-31 | 110.22 | -3.68 |
| 2024-11-30 | 113.35 | +3.13 |
| 2024-12-31 | 115.74 | +2.39 |
| 2025-01-31 | 111.28 | -4.46 |
| 2025-02-28 | 113.12 | +1.84 |
| 2025-03-31 | 111.14 | -1.98 |
| 2025-04-30 | 104.18 | -6.96 |
| 2025-05-31 | 104.72 | +0.54 |
| 2025-06-30 | 105.96 | +1.24 |
| 2025-07-31 | 100.63 | -5.33 |
| 2025-08-31 | 104.35 | +3.72 |
| 2025-09-30 | 104.76 | +0.41 |
| 2025-10-31 | 102.41 | -2.35 |
| 2025-11-30 | 106.13 | +3.72 |
| 2025-12-31 | 107.32 | +1.19 |
| 2026-01-31 | 103.26 | -4.06 |
| 2026-02-28 | 101.96 | -1.30 |
| 2026-03-31 | 95.12 | -6.84 |
| 2026-04-30 | 92.20 | -2.92 |
| 2026-05-31 | 94.40 | +2.20 |
| 2026-06-30 | 97.27 | +2.87 |

## Definition

MSB outstanding is the stock of Monetary Stabilization Bonds (MSB), debt securities issued directly by the Bank of Korea and distinct from Korea Treasury Bonds (국고채) issued by the Ministry of Economy and Finance. Maturities range from 91 days to 2 years, and the outstanding stock typically ranges from 100 to 170 trillion KRW, reflecting the cumulative sterilization of foreign exchange reserve accumulation over decades of current account surpluses and capital inflow management. When the BOK issues an MSB, the purchasing institution pays from its reserve account, permanently reducing reserves until the bond matures.

MSBs have no direct equivalent in the Federal Reserve's toolkit. The Fed's ON RRP facility, which absorbs liquidity on an overnight basis, is the closest functional analogue, but MSBs operate at substantially longer maturities and create structural rather than overnight drains on the reserve position. This structural nature makes MSB outstanding a more persistent component of the Net Liquidity computation than RP sales, which reverse within weeks. Within the Net Liquidity formula, MSB outstanding is subtracted from total assets because the funds used to purchase MSBs are removed from the banking system's reserve base for the duration of the bond's term. A rise in the outstanding stock indicates stronger structural liquidity absorption by the BOK, while a decline indicates its easing.

## Methodology

MSB outstanding is sourced from the Bank of Korea's Key Accounts statistical release and reported as month-end period-end balances. The raw series in billions of KRW is converted to trillions of KRW by dividing by 1,000.

## Applications in Economics

Monetary stabilization bonds are the institutional response to a fundamental tension in Korean monetary policy, namely the need to sterilize the domestic liquidity consequences of foreign exchange reserve accumulation without sacrificing control over the policy interest rate. This sterilization carries a fiscal cost, since sustained intervention in the foreign exchange market creates a quasi-fiscal deficit when the interest paid on sterilization instruments exceeds the return earned on foreign reserve assets (Calvo 1991). For the BOK, this sterilization cost materializes as interest payments on MSBs, which must be funded either through seigniorage or through further MSB issuance, creating a potentially self-reinforcing dynamic.

The effectiveness of sterilization depends on the degree of capital account openness. Kletzer and Spiegel (2004) extend the sterilization cost analysis by incorporating capital controls and demonstrate this dependence. Korea's progressive capital account liberalization since the 1990s has increased the challenge of sterilization, since higher capital mobility reduces the central bank's ability to independently set domestic interest rates while simultaneously managing the exchange rate through reserve accumulation. Ouyang, Rajan, and Willett (2010) provide empirical evidence on sterilization effectiveness across Asian economies and find that Korea has maintained relatively effective sterilization, with MSB issuance successfully offsetting the reserve money impact of foreign exchange intervention.

Emerging market central banks systematically adjust the mix of instruments used for sterilization according to the scale of intervention and the development of domestic capital markets. Aizenman and Glick (2009) document the evolution of sterilized intervention practices across emerging market central banks and show that the balance between securities issuance, reserve requirements, and deposit facilities shifts with these factors. The BOK's heavy reliance on MSB issuance reflects the depth and liquidity of the Korean bond market, which can absorb substantial volumes of central bank debt without severe market distortion.

The BOK's MSB program is one of the largest and most institutionalized sterilization operations in the region. Lavigne (2008) provides a comparative analysis of sterilization bond programs across Asian central banks and confirms this. The structural nature of MSB issuance, with maturities extending to 2 years, creates a predictable maturity profile that shapes the term structure of short-to-medium-term interest rates and affects the relative pricing of MSBs versus government bonds of similar maturity.

## Applications in Financial Markets

For fixed-income investors in the Korean bond market, MSB outstanding is a key supply-side variable that affects the relative pricing of short-to-medium-term fixed-income instruments. Mohanty and Turner (2006) document that foreign exchange reserve accumulation across Asian central banks has generated a substantial supply of sterilization securities, and that this supply influences the term structure of interest rates through a supply-demand channel distinct from monetary policy expectations. The MSB yield curve, which extends from 91 days to 2 years, provides an alternative short-term benchmark alongside KTBs and CDs, and changes in issuance patterns directly affect the relative pricing of these instruments.

The choice of sterilization instrument jointly drives the central bank's cost of intervention and the structure of the domestic bond market. McCauley (2008) analyzes the management of foreign exchange reserves and sterilization operations across central banks and demonstrates this. For Korean market participants, understanding whether the BOK is increasing MSB issuance to sterilize new reserve accumulation or rolling over maturing MSBs at steady levels provides important information about the net liquidity impact of the central bank's operations.

Sterilization operations and base rate changes interact to form a multi-instrument monetary policy framework, where the volume of sterilization securities carries information beyond what the policy rate alone conveys. Cook and Yetman (2012) examine monetary policy transmission in Asian economies and demonstrate this. Filardo and Grenville (2012) extend this analysis to central bank balance-sheet policies more broadly, arguing that the composition of central bank liabilities, including sterilization instruments, shapes financial conditions through portfolio balance and signaling channels.

MSBs constitute a significant fraction of Korea's short-to-medium-term fixed-income market, with implications for liquidity conditions, benchmark pricing, and the relative value between government and central bank securities. Park (2011) provides a detailed analysis of the Korean bond market and documents this. For portfolio managers, changes in MSB outstanding signal shifts in the structural liquidity absorption stance of the BOK, complementing the shorter-term signals available from RP sales and the monetary stabilization account. The Net Liquidity framework integrates these signals into a single composite measure, but tracking the individual components enables more precise identification of the sources of liquidity change.

## Statistical Tests

Over 435 observations from 1990-01-31 to 2026-03-31, the monetary-stabilization-bond outstanding is integrated of order one on the log-level, with the Dickey and Fuller (1979) test in the Said and Dickey (1984) form not rejecting at p = 0.9916, the Phillips and Perron (1988) test concurring at p = 0.9964, and the Kwiatkowski et al. (1992) test rejecting stationarity. On the first difference of the log the Ljung and Box (1978) portmanteau rejects white noise at lags 12 and 24, Q = 42.50 and Q = 58.40 at p = 0.000 and p = 0.000. The Bai and Perron (1998, 2003) procedure finds 2 breaks in the mean at 1997-12-31, 2005-04-30, a reading consistent with the parameter-instability inference of Andrews (1993) on the differenced object (Perron 1989).

This series is an unadjusted monthly aggregate, so the seasonal battery is appropriate and is run, with the HEGY seasonal-unit-root test of Hylleberg et al. (1990), the QS seasonal portmanteau, and the seasonal-dummy F cross-read with Canova and Hansen (1995) finding deterministic seasonality rather than seasonal unit roots (Beaulieu and Miron 1992; Ghysels and Osborn 2001).

## Frequently Asked Questions

### What does the central bank liquidity panel for Korea track?

The components of the domestic central bank balance sheet identity together with the open market operations that add or drain reserves, including repo sales and purchases and the stock of stabilisation securities, plus a net measure of what remains with the private system.

### What does the net open market operations series show?

It nets draining against supplying operations into a single figure, so one number settles whether a period supplied or absorbed on balance. The components are published alongside it.

### How does central bank liquidity differ from the monetary aggregates?

This group measures base liquidity supplied by the central bank; the aggregates measure money and near-money held by the public. The multiplier linking them varies with bank lending behaviour and depositor preferences, so the two track each other only loosely.